This study, which appeared as Chapter 1 in Volume 4 of the Cambridge Medieval History (Cambridge, 1923), was written by the noted Byzantinist Charles Diehl. Topics in Chapter 1 ["Leo III and the Isaurian Dynasty (717-802)"] include: Character of the Period; Leo III the Isaurian; Repulse of the Arabs from Constantinople; Domestic administration (finances, Codes and the Ecloga); Religion: the cult of images; Edict against images (726); Opposition in East and West; Constantine V Copronymus; The revolt of Artavasdus; Successes at home and abroad; Reopening of the iconoclastic struggle; Persecution of image-worshippers; Defeat of the monks; Alienation of Italy and the Papacy; Italy lost to the Empire; Leo IV the Chazar [Khazar]; Regency of Irene; Restoration of images; Irene and Constantine VI; Constantine VI sole ruler: intrigues of Irene; Irene reigns as Emperor; Deposition of Irene; Achievements of the Isaurian Emperors. Includes Title Page, Table of Contents, Chapter 1 (pp. 1-26), Bibliography for Chapter 1 (p. 795-797), Abbreviations, and Chronological Table in 43 pdf pages. Book digitized by Google, article extracted and uploaded by user Robert Bedrosian.